Telkom Contract Cancellation Nightmare

Telkom is the worst network ever I have been trying to cancel my contract from April 2017 and have been going in circles since then , their call centre is a mess . I have made over 100 calls to them , countless emails to and from their reps. Cut off my service in October 2017 but they are still sending me invoices from October til February when I haven't used their services in that time . They just have blatant disregard for their customers